| Abstrakt: |
Leaf herbivory in Miconia albicans(Melastomataceae): an evaluation of leaf position and age –Abstract: Herbivory represents a critical interaction between insects and plants, involving physical defenses like trichomes that enhance plant resistance to herbivorous attacks, while galls—plant tumors— can drain nutrients from healthy tissues. This study aimed to assess foliar herbivory rates and analyze gall incidence in Miconia albicansin a cerrado stricto sensu area near Uberlândia, Minas Gerais, Brazil. From December 2013 to March 2014, herbivory rates were documented biweekly using a digital camera, with subsequent analysis performed using ImageJ software. A Wilcoxon signed-rank test was used to determine significant differences in herbivory rates between young and old leaves, while a GLMM test with beta error distribution followed by a Wald chi-square test examined variations in herbivory rates between high and low leaves. Fifteen plants were selected, marking one young and one old leaf, alongside one high and one low leaf. The incidence of galls was assessed across 50 randomly chosen plants, and the average number of galls per leaf was quantified in another 20 plants. The difference between galled and non-galled branches was analyzed using the Mann-Whitney test. Findings indicated no significant difference in herbivory rates between young and old leaves; however, higher leaves exhibited reduced herbivory rates compared to those in the lower strata, suggesting that leaf position significantly influences herbivory. Galls averaged 19 ± 9 per leaf, predominantly on older leaves. The shaded microclimates of lower strata likely contribute to increased herbivorous insect abundance, underscoring the impact of leaf position on herbivory rates. |
